1 /*- 2 * Copyright (c) 2003-2007 Tim Kientzle 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``AS IS'' AND ANY EXPRESS OR 15 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 16 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 17 * IN NO EVENT SHALL THE AUTHOR(S) BE LIABLE FOR ANY DIRECT, INDIRECT, 18 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 19 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 20 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 21 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 22 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 23 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 24 */ 25 26 #include "archive_platform.h" 27 28 __FBSDID("$FreeBSD$"); 29 30 #ifdef HAVE_ERRNO_H 31 #include <errno.h> 32 #endif 33 #include <stdio.h> 34 #ifdef HAVE_STDLIB_H 35 #include <stdlib.h> 36 #endif 37 #ifdef HAVE_STRING_H 38 #include <string.h> 39 #endif 40 #ifdef HAVE_UNISTD_H 41 #include <unistd.h> 42 #endif 43 #ifdef HAVE_BZLIB_H 44 #include <bzlib.h> 45 #endif 46 47 #include "archive.h" 48 #include "archive_private.h" 49 #include "archive_read_private.h" 50 51 #if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR) 52 struct private_data { 53 bz_stream stream; 54 char *out_block; 55 size_t out_block_size; 56 char valid; /* True = decompressor is initialized */ 57 char eof; /* True = found end of compressed data. */ 58 }; 59 60 /* Bzip2 filter */ 61 static ssize_t bzip2_filter_read(struct archive_read_filter *, const void **); 62 static int bzip2_filter_close(struct archive_read_filter *); 63 #endif 64 65 /* 66 * Note that we can detect bzip2 archives even if we can't decompress 67 * them. (In fact, we like detecting them because we can give better 68 * error messages.) So the bid framework here gets compiled even 69 * if bzlib is unavailable. 70 */ 71 static int bzip2_reader_bid(struct archive_read_filter_bidder *, struct archive_read_filter *); 72 static int bzip2_reader_init(struct archive_read_filter *); 73 74 #if ARCHIVE_VERSION_NUMBER < 4000000 75 /* Deprecated; remove in libarchive 4.0 */ 76 int 77 archive_read_support_compression_bzip2(struct archive *a) 78 { 79 return archive_read_support_filter_bzip2(a); 80 } 81 #endif 82 83 static const struct archive_read_filter_bidder_vtable 84 bzip2_bidder_vtable = { 85 .bid = bzip2_reader_bid, 86 .init = bzip2_reader_init, 87 }; 88 89 int 90 archive_read_support_filter_bzip2(struct archive *_a) 91 { 92 struct archive_read *a = (struct archive_read *)_a; 93 94 if (__archive_read_register_bidder(a, NULL, "bzip2", 95 &bzip2_bidder_vtable) != ARCHIVE_OK) 96 return (ARCHIVE_FATAL); 97 98 #if defined(HAVE_BZLIB_H) && defined(BZ_CONFIG_ERROR) 99 return (ARCHIVE_OK); 100 #else 101 archive_set_error(_a, ARCHIVE_ERRNO_MISC, 102 "Using external bzip2 program"); 103 return (ARCHIVE_WARN); 104 #endif 105 } 106 107 /* 108 * Test whether we can handle this data. 109 * 110 * This logic returns zero if any part of the signature fails. It 111 * also tries to Do The Right Thing if a very short buffer prevents us 112 * from verifying as much as we would like. 113 */ 114 static int 115 bzip2_reader_bid(struct archive_read_filter_bidder *self, struct archive_read_filter *filter) 116 { 117 const unsigned char *buffer; 118 ssize_t avail; 119 int bits_checked; 120 121 (void)self; /* UNUSED */ 122 123 /* Minimal bzip2 archive is 14 bytes. */ 124 buffer = __archive_read_filter_ahead(filter, 14, &avail); 125 if (buffer == NULL) 126 return (0); 127 128 /* First three bytes must be "BZh" */ 129 bits_checked = 0; 130 if (memcmp(buffer, "BZh", 3) != 0) 131 return (0); 132 bits_checked += 24; 133 134 /* Next follows a compression flag which must be an ASCII digit. */ 135 if (buffer[3] < '1' || buffer[3] > '9') 136 return (0); 137 bits_checked += 5; 138 139 /* After BZh[1-9], there must be either a data block 140 * which begins with 0x314159265359 or an end-of-data 141 * marker of 0x177245385090. */ 142 if (memcmp(buffer + 4, "\x31\x41\x59\x26\x53\x59", 6) == 0) 143 bits_checked += 48; 144 else if (memcmp(buffer + 4, "\x17\x72\x45\x38\x50\x90", 6) == 0) 145 bits_checked += 48; 146 else 147 return (0); 148 149 return (bits_checked); 150 } 151 152 #if !defined(HAVE_BZLIB_H) || !defined(BZ_CONFIG_ERROR) 153 154 /* 155 * If we don't have the library on this system, we can't actually do the 156 * decompression. We can, however, still detect compressed archives 157 * and emit a useful message. 158 */ 159 static int 160 bzip2_reader_init(struct archive_read_filter *self) 161 { 162 int r; 163 164 r = __archive_read_program(self, "bzip2 -d"); 165 /* Note: We set the format here even if __archive_read_program() 166 * above fails. We do, after all, know what the format is 167 * even if we weren't able to read it. */ 168 self->code = ARCHIVE_FILTER_BZIP2; 169 self->name = "bzip2"; 170 return (r); 171 } 172 173 174 #else 175 176 static const struct archive_read_filter_vtable 177 bzip2_reader_vtable = { 178 .read = bzip2_filter_read, 179 .close = bzip2_filter_close, 180 }; 181 182 /* 183 * Setup the callbacks. 184 */ 185 static int 186 bzip2_reader_init(struct archive_read_filter *self) 187 { 188 static const size_t out_block_size = 64 * 1024; 189 void *out_block; 190 struct private_data *state; 191 192 self->code = ARCHIVE_FILTER_BZIP2; 193 self->name = "bzip2"; 194 195 state = (struct private_data *)calloc(sizeof(*state), 1); 196 out_block = (unsigned char *)malloc(out_block_size); 197 if (state == NULL || out_block == NULL) { 198 archive_set_error(&self->archive->archive, ENOMEM, 199 "Can't allocate data for bzip2 decompression"); 200 free(out_block); 201 free(state); 202 return (ARCHIVE_FATAL); 203 } 204 205 self->data = state; 206 state->out_block_size = out_block_size; 207 state->out_block = out_block; 208 self->vtable = &bzip2_reader_vtable; 209 210 return (ARCHIVE_OK); 211 } 212 213 /* 214 * Return the next block of decompressed data. 215 */ 216 static ssize_t 217 bzip2_filter_read(struct archive_read_filter *self, const void **p) 218 { 219 struct private_data *state; 220 size_t decompressed; 221 const char *read_buf; 222 ssize_t ret; 223 224 state = (struct private_data *)self->data; 225 226 if (state->eof) { 227 *p = NULL; 228 return (0); 229 } 230 231 /* Empty our output buffer. */ 232 state->stream.next_out = state->out_block; 233 state->stream.avail_out = state->out_block_size; 234 235 /* Try to fill the output buffer. */ 236 for (;;) { 237 if (!state->valid) { 238 if (bzip2_reader_bid(self->bidder, self->upstream) == 0) { 239 state->eof = 1; 240 *p = state->out_block; 241 decompressed = state->stream.next_out 242 - state->out_block; 243 return (decompressed); 244 } 245 /* Initialize compression library. */ 246 ret = BZ2_bzDecompressInit(&(state->stream), 247 0 /* library verbosity */, 248 0 /* don't use low-mem algorithm */); 249 250 /* If init fails, try low-memory algorithm instead. */ 251 if (ret == BZ_MEM_ERROR) 252 ret = BZ2_bzDecompressInit(&(state->stream), 253 0 /* library verbosity */, 254 1 /* do use low-mem algo */); 255 256 if (ret != BZ_OK) { 257 const char *detail = NULL; 258 int err = ARCHIVE_ERRNO_MISC; 259 switch (ret) { 260 case BZ_PARAM_ERROR: 261 detail = "invalid setup parameter"; 262 break; 263 case BZ_MEM_ERROR: 264 err = ENOMEM; 265 detail = "out of memory"; 266 break; 267 case BZ_CONFIG_ERROR: 268 detail = "mis-compiled library"; 269 break; 270 } 271 archive_set_error(&self->archive->archive, err, 272 "Internal error initializing decompressor%s%s", 273 detail == NULL ? "" : ": ", 274 detail); 275 return (ARCHIVE_FATAL); 276 } 277 state->valid = 1; 278 } 279 280 /* stream.next_in is really const, but bzlib 281 * doesn't declare it so. <sigh> */ 282 read_buf = 283 __archive_read_filter_ahead(self->upstream, 1, &ret); 284 if (read_buf == NULL) { 285 archive_set_error(&self->archive->archive, 286 ARCHIVE_ERRNO_MISC, 287 "truncated bzip2 input"); 288 return (ARCHIVE_FATAL); 289 } 290 state->stream.next_in = (char *)(uintptr_t)read_buf; 291 state->stream.avail_in = ret; 292 /* There is no more data, return whatever we have. */ 293 if (ret == 0) { 294 state->eof = 1; 295 *p = state->out_block; 296 decompressed = state->stream.next_out 297 - state->out_block; 298 return (decompressed); 299 } 300 301 /* Decompress as much as we can in one pass. */ 302 ret = BZ2_bzDecompress(&(state->stream)); 303 __archive_read_filter_consume(self->upstream, 304 state->stream.next_in - read_buf); 305 306 switch (ret) { 307 case BZ_STREAM_END: /* Found end of stream. */ 308 switch (BZ2_bzDecompressEnd(&(state->stream))) { 309 case BZ_OK: 310 break; 311 default: 312 archive_set_error(&(self->archive->archive), 313 ARCHIVE_ERRNO_MISC, 314 "Failed to clean up decompressor"); 315 return (ARCHIVE_FATAL); 316 } 317 state->valid = 0; 318 /* FALLTHROUGH */ 319 case BZ_OK: /* Decompressor made some progress. */ 320 /* If we filled our buffer, update stats and return. */ 321 if (state->stream.avail_out == 0) { 322 *p = state->out_block; 323 decompressed = state->stream.next_out 324 - state->out_block; 325 return (decompressed); 326 } 327 break; 328 default: /* Return an error. */ 329 archive_set_error(&self->archive->archive, 330 ARCHIVE_ERRNO_MISC, "bzip decompression failed"); 331 return (ARCHIVE_FATAL); 332 } 333 } 334 } 335 336 /* 337 * Clean up the decompressor. 338 */ 339 static int 340 bzip2_filter_close(struct archive_read_filter *self) 341 { 342 struct private_data *state; 343 int ret = ARCHIVE_OK; 344 345 state = (struct private_data *)self->data; 346 347 if (state->valid) { 348 switch (BZ2_bzDecompressEnd(&state->stream)) { 349 case BZ_OK: 350 break; 351 default: 352 archive_set_error(&self->archive->archive, 353 ARCHIVE_ERRNO_MISC, 354 "Failed to clean up decompressor"); 355 ret = ARCHIVE_FATAL; 356 } 357 state->valid = 0; 358 } 359 360 free(state->out_block); 361 free(state); 362 return (ret); 363 } 364 365 #endif /* HAVE_BZLIB_H && BZ_CONFIG_ERROR */ 366